THA analogs useful as cholinesterase inhibitors

ABSTRACT

The present invention provides cholinesterase inhibitors of general formula (I): ##STR1## wherein R is H or (C 1  -C 4 )alkyl, Y is a linking group and Z is an alkyl or aryl group, including heteroaryl groups, and the pharmaceutically acceptable salts thereof.

BACKGROUND OF THE INVENTION

Alzheimer's Disease is a devastating neurodegenerative disorder which ischaracterized by dramatic personality changes and global cognitivedecline. It currently affects approximately four million Americans,taking more than 100,000 lives each year. See, R. Tanzi et al.,Genetica, 91, 255 (1993). As described by D. J. Selkoe, Neuron, 6, 487(1991) and Z. S. Khachaturian, Arch. Neurol., 42, 1097 (1989), thisdisease is pathologically characterized by the degeneration of the basalforebrain cholinergic system and the deposit of amyloid plaques in thebrain.

One approach to treating this disease is to restore the level ofneurotransmitter acetylcholine, which is found to be lowered in brainsof the Alzheimer's patients, by inhibiting acetylcholinesterase (AChE)with reversible inhibitors. One class of AChE inhibitors includeshuperzine A and analogs thereof. See, for example, Kozikowski (U.S. Pat.No. 5,104,880). Another such AChE inhibitor9-amino-1,2,3,4-tetrahydroacridine (THA, also known as tacrine orCOGNEX) is currently a drug approved by the United States Food and DrugAdministration for the palliative treatment of mild and moderateAlzheimer's Disease. See, K. L. Davis et al., Lancet, 345, 625 (1995).The structure of THA is depicted below. ##STR2##

However, the use of THA is currently limited by its serioushepatoxicity. Therefore, there is a continuing need for AChE inhibitorswhich may be useful to treat Alzheimer's Disease, including analogs ofTHA exhibiting improved profiles of bioactivity, such as higher potency,and a lower incidence or intensity of side effects.

SUMMARY OF THE INVENTION

The present invention provides cholinesterase inhibitors of the generalformula (I): ##STR3## where R is H or (C₁ -C₄)alkyl, Y is (C₄-C₁₅)alkylene or (C₄ -C₁₅)alkylene N(R)-- and Z is (C₃ -C₁₂)alkyl or a5-18 membered aryl ring, optionally substituted with CH═NOH andoptionally comprising 1-3 N(X), S, non-peroxide O or mixtures thereof,wherein X is absent or is H or (C₁ -C₄)alkyl; or a pharmaceuticallyacceptable salt thereof.

Thus, one embodiment of the present invention provides bioactive THA(tacrine) analogs of the general formula (II): ##STR4## where R is H or(C₁ -C₄)alkyl, Y is (C₄ -C₁₅)alkylene or (C₄ -C₁₅)alkylene N(R)-- and Aris a 5-18 membered aryl ring, optionally comprising 1-3 N(X), S,non-peroxide O or mixtures thereof, wherein X is absent or is H or (C₁-C₄)alkyl; or a pharmaceutically acceptable salt thereof.

Preferably, R is H or methyl. Y is preferably --(CH₂)_(n) -- or--(CH₂)_(n) --N(R)--, wherein n is 4-15, preferably 5-13, mostpreferably 6-10. Thus, preferred compounds are1,7-ω-n-alkylene-bis-9,9'-amino- 1,2,3-4-tetrahydroacridines, wherein nis 7-10. The term "aryl ring" includes mono-, bi- and tricyclic ringsystems, optionally substituted by CH--NOH, which ring systems compriseat least one aryl ring. Ar is preferably (C₆ -C₁₄)aryl, optionallycomprising 1-2 (X)N, i.e., phenyl, indanyl, indanonyl, naphthyl,indenyl, pyridinyl, pyridonyl, or 1,2,3,4-tetrahydro-acridine-9-yl. Theterm "alkyl" as used herein includes straight- and branched-chain alkyl,cycloalkyl, alkyl(cycloalkyl), alkyl(cycloalkyl)alkyl, and(cycloalkyl)(alkyl), optionally comprising 1-2 N(X), S, or O and/or 1-3double bonds. The term "cycloalkyl" also includes bicyclo-, tricyclo-and tetracycloalkyl. Z is preferably a secondary or tertiary alkyl groupsuch as isopropyl, t-butyl, or 3-pentyl, which may contain furtherbranching, or cycloalkyl such as cyclopentyl, cyclohexyl, norbornyl, oradamantyl.

The compounds of formula (I), particularly those of formula (II), werefound to be up to about 7,000-fold more selective and 1,000-fold morepotent in reversably inhibiting AChE than THA. Thus, the presentcompounds are useful (i) to evaluate the role of AChE inhibition by THAin treating Alzheimer's Disease, (ii) as potential, prophylactic ortherapeutic antidotes for chemical warfare agents and fororganophosphate insecticides (i.e., organophosphate poisoning) (see, P.X. Chiang et al., U.S. Pat. No. 5,026,897); (iii) as potential drugs forkilling parasites, (iv) as insecticides (see Wilson et al., Biochim.Biophys. Acta., 18, 168 (1955)), (v) as potential blockers of K⁺ channeland the N-methyl-D-aspartate receptor channel (see J. Patocka et al.,Collect. Czech. Chem. Commun., 41, 816 (1976); D. Galanakis et al., J.Med. Chem., 38, 595 (1995) and M. E. Nelson et al., Mol. Pharmacol., 46,151 (1994)); (vi) as therapeutic agents for the treatment of Alzheimer'sDisease and other neurological conditions which can be ameliorated bythe inhibition of AChE activity and/or BChE activity in a mammal such asa human, afflicted with said condition, and (vii) as reversible,selective, and potent butyrylcholinesterase (BChE) inhibitors to affectalterations in the permissive or causative role BChE in theneuropathology of AD or other dementing illness.

Thus, the present invention also provides pharmaceutical, parasiticidalor insecticidal compositions comprising an effective amount of one ormore compounds of formula (I) in combination with an acceptable carriervehicle for a pharmaceutical, parasiticidal, or insecticidalcomposition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts the structures of analogs 1a-d and 2a-g.

FIG. 2 schematically depicts the synthesis of ditosylate 10 and THAanalogs 1a-d.

FIG. 3 schematically depicts the synthesis of analogs 2a-g.

FIG. 4 depicts structures of analogs of formula (I) wherein Z is alkyl.

FIG. 5 depicts plots of the inhibition of rat AChE, BChE, and normalizedIC₅₀ (AChE inhibition) by compounds of the invention.

FIG. 6 depicts plots of the substrate kinetics of human brain ACHEinhibition by 1a (Panel A) and THA (Panel B).

DETAILED DESCRIPTION OF THE INVENTION

Analogs (1a-d) were readily prepared as shown in FIG. 2. Thecommercially available l,ω-alkanediol (n=7-10) was first converted tobistosylate in about 40% yield by reacting the alcohol with twoequivalents of tosyl chloride in pyridine. The bis-tosylate was thenreacted at room temperature with two equivalents of THA anion, preparedby reacting THA in its base form with sodium amide, to yield thedesigned analog in series 1.

Analogs (2a-g) were prepared according to FIG. 3. The commerciallyavailable N-phenyl-l-alkyl alcohol (n=4-10) was first converted totosylate in about 95% yield by reacting the alcohol with tosyl chloridein pyridine. The tosylate was then reacted at room temperature with oneequivalent of the THA anion prepared as above to yield the desiredanalog.

One of ordinary skill in the art can readily prepare other analogs offormula (I) by substituting compounds of general formula TsO--Y--Ar orTsO--Y--Alkyl for compound 12 in FIG. 3. The aryl group (Ar) is asdefined above, e.g., Ar can be a C₆ -C₁₈, aryl moiety, such as phenyl,naphthyl, 1,2,3,4-tetrahydronaphthyl, or a heteroaryl, i.e. aheteroaromatic ring system, such as pyridine, furan, thiophene, pyrrole,acridine, 1,2,3,4-tetrahydroacridine, imidazole, pyrazole, oxazole,isoxazole, indole, indanyl, benzofuran, benzothiophene, quinoline,isoquinoline, carbazole, isothiazole, thiazole, pyridazine, pyrimidine,or pyrazine, and the like.

Mono-substituted amino compounds of formula I, wherein R is (C₁-C₄)alkyl, aryl, or aralkyl can be prepared by conventional methods forthe conversion of secondary amino groups to tertiary amino groups. Forexample, see I. T. Harrison et al., Compendium of Organic SyntheticMethods, Wiley-Interscience, N.Y. (1971) at pages 240-246.

The oxime substituted compounds of formula (I) can be prepared byconverting the carbonyl group, which should be protected in the reactionof coupling to the THA moiety, of the indanone derivatives to an oximegroup. See, I. T. Harrison et al., Compendium, cited above, at page 235;J. Biol. Chem., 211, 725 (1954); J. Amer. Chem. Soc., 50, 3370 (1928).

Pharmaceutically acceptable acid salts of the present compounds can beprepared as described in U.S. Pat. No. 4,383,114.

The compounds of formula I can be employed, singly or in combination, inan amount effective to inhibit the cholinesterase enzymes (such as BChEor AChE) in an insect or a mammal (such as a human). Therefore, thepresent invention also includes a pharmaceutical composition, such asone or more unit dosage forms, of an effective cholinesteraseenzyme-inhibiting amount of one or more of the compounds of formula I incombination with a pharmaceutically acceptable carrier therefor. Suchtherapeutic compositions can be administered orally or parenterally,including via intravenous, intramuscular, intraperitoneal, subcutaneous,or topical administration.

For oral use of a compound of general formula I, said compound can beadministered, for example, in the form of tablets or capsules, or as anaqueous solution or suspension. In the case of tablets for oral use,carriers which are commonly used include lactose, mannitol and cornstarch, and lubricating agents, such as magnesium stearate, are commonlyadded. For oral administration in capsule form, the compound can beadministered in dry form in a hard gelatin capsule or in a suitablegelled or liquid vehicle, such as a liquid polyethylene glycol or acarrageenan gel, in a soft gelatin capsule. When aqueous suspensions arerequired for oral use, the active ingredient is combined withemulsifying and suspending agents. If desired, certain sweetening and/orflavoring agents may be added. For intramuscular, intraperitoneal,subcutaneous and intravenous use, sterile solutions of the activeingredient are usually prepared, and the pH of the solutions should besuitably adjusted and buffered. For intravenous infusion or injection,the total concentration of solutes should be controlled in order torender the preparations isotonic.

When a compound according to general formula I is used as in a humansubject, the daily dosage will normally be determined by the prescribingphysician with the dosage generally varying according to the age,weight, and response of the individual patient, as well as the severityof the patient's symptoms. However, in most instances, an effectivedaily dosage will be in the range of from about 0.05 mg/kg to about 25mg/kg of body weight, and preferably, of from 0.1 mg/kg to about 10mg/kg of body weight, administered in single or divided doses. In somecases, however, it may be necessary to use dosages outside these limits.Useful dosages may be calculated, to some extent, or those found to beeffective when other AChE inhibitors, such as huperzine A, areadministered to animals or humans. See, for example, C. Tang et al.,Acta Pharmacol. Sinica, 7, 507 (1986); G. P. Vincent et al., NeurosciAbstr. 13, 884 (1987); and Y. -S. Cheng, New Drugs and ClinicalRemedies, 5, 197 (1986).

For insecticidal or parasiticidal uses, the compounds of the inventioncan be coated, sprayed, or dusted onto the target surface ascompositions comprising suitable carriers, such as inert powdered solidsor liquids, optionally containing surfactants, dispersing agents, andother adjuvants.

The invention will be further described by reference to the followingdetailed examples, wherein tetrahydrofuran (THF) was distilled fromsodium benzophenone ketyl prior to use. Solvents used for chromatographywere purchased in 5-gal drums. Silica gel 60 (Merck, 230-400 mesh ASTMfor flash chromatography) was used for column chromatography. TLC wasperformed on Merck silica gel 60F-254 (0.25 mm, precoated on glass).Other reagents were used as supplied by the Aldrich Chemical Co. andLancaster Synthesis Inc.

Chemical shifts are reported in delta units with reference to (CH₃)₄ Si(δ=0.00 ppm) for ¹ H or CDCl₃ (δ=77.00 ppm) for ¹³ C as internalstandards.

EXAMPLE 1 Toluene-4-sulfonic Acid 7-Toluene-4-sulfonyloxy-heptyl Ester

Pyridine (7 mL) was added to 4326 mg (22.7 mmol) of p-toluenesulfonylchloride at room temperature under N₂. The color of the solution changedimmediately to yellow after addition. 1,7-heptanediol (1000 mg, 7.6mmol) in 7 mL of pyridine was then added dropwise to the solution at 0°C. The resulting solution was stirred at 0° C. for 30 minutes, slowlywarmed to room temperature, and then stirred at room temperature for 24hours. White precipitates were generated and the color of the solutionturned to brownish. The tosylate was extracted with CHCl₃ and washedwith saturated NH₄ Cl. Flash chromatography on silica gel eluting with30% EtOAc in hexane yielded 1332 mg (40%) of the tosylate as whitecrystals: ¹ H NMR (CDCl₃, 300 Mz) δ 7.79 (d, J=9.0 Hz, 4 H), 7.35 (d,J=9.0 Hz, 4 H), 3.99 (t, J=6.0 Hz, 4 H), 2.45 (s, 6 H), 1.68-1.54 (m, 4H), 1.36-1.18 (m, 6 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.60, 132.80,129.66, 127.59, 70.32, 28.37, 27.95, 24.88, 21.39.

EXAMPLE 2 Toluene-4-sulfonic Acid 8-Toluene-4-sulfonyloxy-octyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 7-toluene-4-sulfonyloxy-heptyl ester was followed to afford theproduct as white crystals: H NMR (CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz, 4H), 7.35 (d, J=9.0 Hz, 4 H), 4.00 (t, J=6.0 Hz, 4 H), 2.45 (s, 6 H),1.68-1.58 (m, 4 H), 1.38-1.16 (m, 8 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ144.65, 133.05, 129.76, 127.78, 70.50, 28.64, 28.57, 25.10, 21.56.

EXAMPLE 3 Toluene-4-sulfonic Acid 9-Toluene-4-sulfonyloxy-nonyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 7-toluene-4-sulfonyloxy-heptyl ester was followed to afford theproduct as white crystals: ¹ H NMR (CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz,4 H), 7.35 (d, J=9.0 Hz, 4 H), 4.01 (t, J=6.0 Hz, 4 H), 2.45 (s, 6 H),1.78-1.58 (m, 4 H), 1.36-1.18 (m, 10 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ144.58, 132.93, 129.69, 127.67, 70.53, 28.90, 28.56, 25.08, 21.45.

EXAMPLE 4 Toluene-4-sulfonic Acid 10-Toluene-4-sulfonyloxy-decyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 7-toluene-4-sulfonyloxy-heptyl ester was followed to afford theproduct as white crystals: ¹ H NMR (CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz,4 H), 7.35 (d, J=9.0 Hz, 4 H), 4.01 (t, J=6.0 Hz, 4 H), 2.45 (s, 6 H),1.68-1.58 (m, 4 H), 1.35-1.16 (m, 12 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ144.60, 133.10, 129.74, 127.78, 70.61, 29.10, 28.74, 25.21, 21.56.

EXAMPLE 5 1-7-n-Heptylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine (1a)

A solution of 1015 mg (5.1 mmol) of THA in 4 mL of THF was added to thesuspension of 240 mg (6.2 mmol) of NaNH₂ in 4 mL of THF under N₂. Themixture was vigorously stirred at room temperature for 45 minutes. Asolution of 749 mg (1.7 mmol) of toluene-4-sulfonic acid7-toluene-4-sulfonyloxy-heptyl ester in 8 mL of THF was then added tothe orange-red mixture and kept stirring at room temperature for 50hours. The product was extracted with EtOAc and washed with saturatedNa₂ CO₃. Flash chromatography on NH₃ saturated silica gel eluting with5% methanol in CHCl₃ afforded 318 mg (38%) of the product as a yellowoil: IR (CDCl₃) 3347, 3061, 2932, 2859, 2180, 1615, 1580, 1562, 1499,1420, 1358, 1296, 1273, 1167, 1130, 941, 909, 762, 731, 679, 640 cm⁻¹ ;¹ H NMR (CDCl₃, 300 MHz) δ 7.94 (d, J=9.0 Hz, 2 H), 7.90 (d, J=9.0 Hz, 2H), 7.55 (t, J=8.0 Hz, 2 H), 7.34 (t, J=5.0 Hz, 2 H), 3.91 (s, 2 H),3.54-3.38 (m, 4 H), 3.11-2.99 (m, 4 H), 2.78-2.66 (m, 4 H), 1.99-1.85(m, 8 H), 1.71-1.57 (m, 4 H), 1.46-1.31 (m, 6 H); ¹³ C NMR (CDCl₃, 75.46MHz) δ 158.35, 150.49, 147.40, 128.65, 128.04, 123.38, 122.65, 120.11,115.79, 49.25, 33.96, 31.52, 28.95, 26.67, 24.65, 22.90, 22.65.

EXAMPLE 6 1-8-n-Octylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine (1b)

The same procedure as employed in the preparation of1-7-n-heptylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine was followedto afford the product as a yellow oil: IR (CDCl₃) 3347, 3063, 2932,2857, 2182, 1615, 1582, 1564, 1503, 1420, 1360, 1298, 1273, 1130, 939,909, 762, 731, 640 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.95 (d, J=9.0 Hz,2 H), 7.90 (d, J=9.0 Hz, 2 H), 7.55 (t, J=8.0 Hz, 2 H), 7.34 (t, J=5.0Hz, 2 H), 3.92 (s, 2 H), 3.47 (t, J=8.0 Hz, 4 H), 3.11-2.99 (m, 4 H),2.78-2.66 (m, 4 H), 2.00-1.83 (m, 8 H), 1.71-1.54 (m, 4 H), 1.45-1.21(m, 8 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.38, 150.55, 147.45, 128.70,128.06, 123.40, 122.70, 120.14, 115.79, 49.34, 34.00, 31.60, 29.12,26.69, 24.68, 22.95, 22.70.

EXAMPLE 7 1-9-n-Nonylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine (1c)

The same procedure as employed in the preparation of1-7-n-heptylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine was followedto afford the product as a yellow oil: IR (CDCl₃) 3356, 3063, 2930,2857, 2182, 1615, 1582, 1564, 1505, 1418, 1360, 1298, 1273, 1130, 909,762, 731, 681, 640 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.95 (d, J=9.0 Hz,2 H), 7.90 (d, J=9.0 Hz, 2 H), 7.55 (t, J=8.0 Hz, 2 H), 7.34 (t , J=5.0Hz, 2 H), 3.93 (s, 2 H), 3.47 (t, J=6.0 Hz, 4 H), 3.11-2.99 (m, 4 H),2.78-2.66 (m, 4 H), 1.99-1.85 (m, 8 H), 1.73-1.55 (m, 4 H), 1.44-1.21(m, 10 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.32, 150.54, 147.42, 128.64,128.01, 123.35, 122.68, 120.11, 115.71, 49.31, 33.95, 31.60, 29.23,29.08, 26.72, 24.64, 22.92, 22.66.

EXAMPLE 8 1-10-n-Decylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine (1d)

The same procedure as employed in the preparation of1-7-n-heptylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine was followedto afford the product as a yellow oil: IR (CDCl₃) 3345, 3063, 2928,2855, 2182, 1615, 1582, 1564, 1503, 1420, 1360, 1296, 1169, 1130, 941,909, 762, 731, 679 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.96 (d, J=9.0 Hz,2 H), 7.90 (d, J=9.0 Hz, 2 H), 7.55 (t, J=8.0 Hz, 2 H), 7.34 (t, J=5.0Hz, 2 H), 3.93 (s, 2 H), 3.47 (t, J=8.0 Hz, 4 H), 3.11-2.99 (m, 4 H),2.78-2.66 (m, 4 H), 1.99-1.85 (m, 8 H), 1.72-1.55 (m, 4 H), 1.44-1.22(m, 12 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.34, 150.60, 147.44, 128.65,128.06, 123.38, 122.73, 120.12, 115.71, 49.38, 33.97, 31.65, 29.28,29.18, 26.78, 24.67, 22.95, 22.70.

EXAMPLE 9 Toluene-4-sulfonic Acid 4-Phenyl-butyl Ester

Pyridine (10 mL) was added to 1487 mg (7.8 mmol) of p-toluenesulfonylchloride at room temperature under N₂. The color of the solution changedimmediately to yellow after addition. 4-Phenyl-1-butanol (781 mg, 5.2mmol) was then added dropwise to the solution. The resulting solutionwas stirred at room temperature for three hours. White precipitates weregenerated and the color of the solution turned to brownish. The tosylatewas extracted with EtOAc and washed with saturated NH₄ Cl. Flashchromatography on silica gel eluting with 10% EtOAc in hexane yielded1503 mg (95%) of the tosylate as a colorless oil: IR (CDCl₃) 3061, 3028,2945, 2861, 1923, 1807, 1659, 1599, 1495, 1454, 1360, 1308, 1292, 1177,1098, 1018, 936, 816 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.78 (d, J=9.0Hz, 2 H), 7.33 (d, J=6.0 Hz, 2 H), 7.28-7.24 (m, 2 H), 7.20-7.15 (m, 1H), 7.10 (d, J=6.0 Hz, 2 H), 4.03 (t, J=6.0 Hz, 2 H), 2.56 (t, J=6.0 Hz,2 H), 2.44 (s, 3 H), 1.74-1.57 (m, 4 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ144.51, 141.31, 132.81, 129.63, 128.09, 127.56, 125.64, 70.22, 34.78,28.03, 26.81, 21.34.

EXAMPLE 10 Toluene-4-sulfonic Acid 5-Phenyl-pentyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3063, 3027, 2938, 2859, 1923, 1807, 1599,1495, 1454, 1358, 1175, 1098, 1030, 947, 910, 814, 748, 700, 664 cm⁻¹ ;¹ H NMR (CDCl₃, 300 MHz) δ 7.78 (d, J=9.0 Hz, 2 H), 7.33 (d, J=9.0 Hz, 2H), 7.29-7.24 (m, 2 H), 7.20-7.17 (m, 1 H), 7.12 (d, J=6.0 Hz, 2 H),4.01 (t, J=6.0 Hz, 2 H), 2.56 (t, J=8.0 Hz, 2 H), 2.44 (s, 3 H),1.71-1.62 (m, 2 H), 1.59-1.51 (m, 2 H), 1.39-1.31 (m, 2 H); ¹³ C NMR(CDCl₃, 75.46 MHz) δ 144.35, 141.78, 132.76, 129.51, 127.95, 127.90,127.43, 126.98, 125.36, 70.17, 35.23, 30.31, 28.25, 24.57, 21.17.

EXAMPLE 11 Toluene-4-sulfonic Acid 6-Phenyl-hexyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3061, 3027, 2932, 2857, 2361, 2342, 1599,1495, 1454, 1360, 1177, 1098, 959, 918, 816, 748, 700, 665 cm⁻¹ ; ¹ HNMR (CDCl₃, 300 MHz) δ 7.78 (d, J=9.0 Hz, 2 H), 7.34 (d, J=9.0 Hz, 2 H),7.29-7.25 (m, 2 H), 7.19-7.13 (m, 3 H), 4.01 (t, J=6.0 Hz, 2 H), 2.56(t, J=8.0 Hz, 2 H), 2.44 (s, 3 H), 1.65-1.54 (m, 4 H), 1.36-1.23 (m, 4H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.40, 142.15, 132.86, 129.55,128.03, 127.95, 127.51, 125.35, 70.34, 35.42, 30.87, 28.39, 28.20,24.88, 21.26.

EXAMPLE 12 Toluene-4-sulfonic Acid 7-Phenyl-heptyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3061, 3027, 2930, 2857, 1599, 1495, 1454,1360, 1177, 1098, 1020, 961, 930, 816, 748, 700, 664, 575, 556 cm⁻¹ ; ¹H NMR (CDCl₃, 300 MHz) δ 7.78 (d, J=9.0 Hz, 2 H), 7.33 (d, J=6.0 Hz, 2H), 7.29-7.25 (m, 2 H), 7.19-7.14 (m, 3 H), 4.01 (t, J=6.0 Hz, 2 H),2.57 (t, J=8.0 Hz, 2 H), 2.44 (s, 3 H), 1.65-1.52 (m, 4 H), 1.39-1.21(m, 6 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.47, 142.43, 132.99, 129.62,128.15, 128.03, 127.62, 125.41, 70.45, 35.64, 31.09, 28.77, 28.54,25.04, 21.37.

EXAMPLE 13 Toluene-4-sulfonic Acid 8-Phenyl-octyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3061, 3027, 2926, 2855, 1923, 1807, 1655,1599, 1495, 1454, 1358, 1306, 1292, 1177, 1098, 1030, 941, 814, 748,700, 664 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz, 2 H), 7.33(d, J=6.0 Hz, 2 H), 7.27-7.25 (m, 2 H), 7.19-7.15 (m, 3 H), 4.01 (t,J=6.0 Hz, 2 H), 2.58 (t, J=8.0 Hz, 2 H), 2.44 (s, 3 H), 1.64-1.55 (m, 4H), 1.35-1.20 (m, 8 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.47, 142.55,133.01, 129.64, 128.18, 128.04, 127.66, 125.41, 70.50, 35.73, 31.23,29.04, 28.91, 28.60, 25.10, 21.41.

EXAMPLE 14 Toluene-4-sulfonic Acid 9-Phenyl-nonyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3063, 3027, 2928, 2855, 1599, 1495, 1454,1360, 1177, 953, 916, 816, 748, 700, 664, 577, 556 cm⁻¹ ; ¹ H NMR(CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz, 2 H), 7.34 (d, J=9.0 Hz, 2 H),7.30-7.25 (m, 2 H), 7.19-7.16 (m, 3 H), 4.01 (t, J=6.0 Hz, 2 H), 2.59(t, J=8.0 Hz, 2 H), 2.44 (s, 3 H), 1.65-1.57 (m, 4 H), 1.35-1.17 (m, 10H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.49, 142.68, 133.08, 129.68,128.23, 128.09, 127.71, 125.44, 70.56, 35.81, 31.34, 29.15, 29.09,28.75, 28.64, 25.16, 21.47.

EXAMPLE 15 Toluene-4-sulfonic Acid 10-Phenyl-decyl Ester

The same procedure as employed in the preparation of toluene-4-sulfonicacid 4-phenyl-butyl ester was followed to afford the product as acolorless oil: IR (CDCl₃) 3061, 3027, 2926, 2855, 1921, 1805, 1653,1599, 1495, 1454, 1360, 1306, 1292, 1177, 1098, 1020, 959, 928, 816 cm⁻¹; ¹ H NMR (CDCl₃, 300 MHz) δ 7.79 (d, J=9.0 Hz, 2 H), 3.34 (d, J=9.0 Hz,2 H), 7.30-7.25 (m, 2 H), 7.18-7.16 (m, 3 H), 4.01 (t, J=6.0 Hz, 2 H),2.59 (t, J=8.0 Hz, 2 H), 2.44 (s, 3 H), 1.65-1.57 (m, 4 H), 1.28-1.21(m, 12 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 144.52, 142.79, 133.20, 129.71,128.31, 128.14, 127.79, 125.47, 70.62, 35.89, 31.41, 29.33, 29.26,29.20, 28.81, 28.73, 25.24, 21.53.

EXAMPLE 16 (4-Phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2a)

A solution of 458 mg (2.3 mmol) of THA in 5 mL of THF was added to thesuspension of 180 mg (4.6 mmol) of NaNH₂ in 2 mL of THF under N₂. Themixture was vigorously stirred at room temperature for 45 minutes. Asolution of 700 mg (2.3 mmol) of toluene-4-sulfonic acid 4-phenyl-butylester in 14 mL of THF was then added to the orange-red mixture and keptstirring at room temperature for 24 hours. The product was extractedwith EtOAc and washed with saturated Na₂ CO₃. Flash chromatography onNH₃ saturated silica gel eluting with 30% EtOAc in hexane afforded 509mg (67%) of the product as a yellow oil: IR (CDCl₃) 3351, 3061, 3025,2934, 2859, 1655, 1615, 1582, 1562, 1497, 1452, 1420, 1362, 1333, 1142,943, 856, 762, 700 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.91 (t, J=9.0 Hz,2 H), 7.55-7.52 (m, 1 H), 7.36-7.26 (m, 3 H), 7.21-7.14 (m, 3 H), 3.89(s, 1 H), 3.49 (t, J=8.0 Hz, 2 H), 3.11-2.99 (m, 2 H), 2.70-2.56 (m, 4H), 1.96-1.87 (m, 4 H), 1.77-1.67 (m, 4 H); ¹³ C NMR (CDCl₃, 75.46 MHz)δ 158.34, 150.48, 147.42, 141.73, 128.68, 128.20, 128.06, 125.74,123.43, 122.65, 120.17, 115.90, 49.13, 35.39, 33.97, 31.10, 28.53,24.63, 22.90, 22.66.

EXAMPLE 17 (5-Phenyl-pentyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2b)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3347, 3061, 3025,2932, 2857, 1615, 1603, 1562, 1497, 1452, 1420, 1358, 1298, 1125, 939,909, 762, 700 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.91 (t, J=9.0 Hz, 2 H),7.59-7.50 (m, 1 H), 7.36-7.25 (m, 3 H), 7.20-7.14 (m, 3 H), 3.90 (s, 1H), 3.54-3.42 (m, 2 H), 3.10-2.98 (m, 2 H), 2.69-2.59 (m, 4 H),1.93-1.90 (m, 4 H), 1.71-1.61 (m, 4 H), 1.47-1.39 (m, 2 H); ¹³ C NMR(CDCl₃, 75.46 MHz) δ 158.17, 150.32, 147.34, 141.92, 128.57, 128.06,128.01, 127.87, 125.46, 123.23, 122.59, 120.00, 115.60, 49.06, 35.45,33.89, 31.30, 30.78, 26.16, 24.48, 22.79, 22.54.

EXAMPLE 18 (6-Phenyl-hexyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2c)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3345, 3061, 3025,2930, 2857, 1615, 1582, 1562, 1497, 1454, 1420, 1360, 1298, 1125, 941,909, 762, 698 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.92 (dd, J=9.0, 15.0Hz, 2 H), 7.60-7.50 (m, 1 H), 7.36-7.25 (m, 3 H), 7.20-7.15 (m, 3 H),3.92 (s, 1 H), 3.49-3.45 (m, 2 H), 3.11-3.01 (m, 2 H), 2.77-2.65 (m, 2H), 2.60 (t, J=8.0 Hz, 2 H), 1.96-1.90 (m, 4 H), 1.67-1.58 (m, 4 H),1.48-1.35 (m, 4 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.33, 150.51,147.47, 142.35, 128.71, 128.20, 128.11, 128.04, 125.52, 123.37, 122.69,120.14, 115.74, 49.32, 35.66, 34.01, 31.55, 31.16, 28.81, 26.67, 24.66,22.94, 22.69.

EXAMPLE 19 (7-Phenyl-heptyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2d)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3347, 3061, 3025,2930, 2855, 1615, 1603, 1562, 1497, 1454, 1420, 1360, 1123, 1028, 943,762, 698 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.92 (dd, J=9.0, 15.0 Hz, 2H), 7.54 (t, J=8.0 Hz, 1 H), 7.36-7.19 (m, 3 H), 7.17-7.15 (m, 3 H),3.92 (s, 1 H), 3.49-3.46 (m, 2 H), 3.11-2.99 (m, 2 H), 2.78-2.66 (m, 2H), 2.59 (t, J=8.0 Hz 2 H), 1.94-1.90 (m, 4 H), 1.67-1.58 (m, 4 H),1.41-1.33 (m, 6 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.33, 150.54,147.50, 142.51, 128.73, 128.21, 128.09, 125.47, 123.35, 122.71, 120.14,115.71, 49.35, 35.75, 34.03, 31.62, 31.21, 29.09, 28.98, 26.72, 24.65,22.95, 22.70.

EXAMPLE 20 (8-Phenyl-octyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2e)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3354, 3061, 3025,2928, 2855, 1615, 1582, 1562, 1497, 1454, 1420, 1358, 1296, 1273, 1121,1028, 943, 909, 760, 698 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.92 (dd,J=9.0, 15 Hz, 2 H), 7.60-7.50 (m, 1 H), 7.36-7.24 (m, 3 H), 7.19-7.15(m, 3 H), 3.92 (s, 1 H), 3.49-3.42 (m, 2 H), 3.06-3.04 (m, 2 H),2.78-2.66 (m, 2 H), 2.59 (t, J=9.0 Hz, 2 H), 1.94-1.87 (m, 4 H),1.67-1.58 (m, 4 H), 1.40-1.31 (m, 8 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ158.46, 150.68, 147.56, 142.73, 128.79, 128.32, 128.17, 125.53, 123.47,122.80, 120.23, 115.83, 49.50, 35.89, 34.10, 31.74, 31.38, 29.32, 29.23,29.12, 26.87, 24.75, 23.04, 22.79.

EXAMPLE 21 (9-Phenyl-nonyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2f)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3354, 3061, 3027,2928, 2855, 2180, 1615, 1582, 1564, 1497, 1454, 1418, 1360, 1298, 1121,941, 909, 760, 698 cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.93 (dd, J=9.0,18.0 Hz, 2 H), 7.60-7.49 (m, 1 H), 7.36-7.25 (m, 3 H), 7.19-7.16 (m, 3H), 3.92 (s, 1 H), 3.49-3.45 (m, 2 H), 3.06-3.04 (m, 2 H), 2.76-2.65 (m,2 H), 2.59 (t, J=8.0 Hz, 2 H), 1.94-1.90 (m, 4 H), 1.67-1.58 (m, 4 H),1.40-1.29 (m, 10 H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.18, 150.46,147.38, 142.54, 128.59, 128.12, 127.95, 125.31, 123.23, 122.65, 120.03,115.55, 49.25, 35.72, 33.91, 31.52, 31.24, 29.19, 29.14, 29.01, 26.67,24.54, 22.84, 22.59.

EXAMPLE 22 (10-Phenyl-decyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine(2g)

The same procedure as employed in the preparation of(4-phenyl-butyl)-(1,2,3,4-tetrahydro-acridine-9-yl)-amine was followedto afford the product as a yellow oil: IR (CDCl₃) 3370, 3061, 3025,2926, 2855, 1657, 1582, 1562, 1497, 1454, 1420, 1362, 1123, 762, 698cm⁻¹ ; ¹ H NMR (CDCl₃, 300 MHz) δ 7.93 (dd, J=9.0, 18.0 Hz, 2 H),7.60-7.50 (m, 1 H), 7.37-7.25 (m, 3 H), 7.19-7.14 (m, 3 H), 3.93 (s, 1H), 3.54-3.42 (m, 2 H), 3.11-2.99 (m, 2 H), 2.76-2.66 (m, 2 H), 2.59 (t,J=8.0, 2 H), 1.94-1.90 (m, 4 H), 1.67-1.58 (m, 4 H), 1.40-1.27 (m, 12H); ¹³ C NMR (CDCl₃, 75.46 MHz) δ 158.42, 150.65, 147.55, 142.79,128.77, 128.29, 128.12, 125.47, 123.43, 122.78, 120.20, 115.79, 49.48,35.89, 34.08, 31.71, 31.41, 29.41, 29.37, 29.28, 29.23, 26.86, 24.73,23.01, 22.76.

EXAMPLE 23 Pharmacological Activity

Representative compounds of formula II in their salt form were tested invitro for selectivity and potency as cholinesterase inhibitors. Ratbrain homogenate prepared in 10 ml/g 10 mM Tris, pH 7.4, plus 1% TritonX-100 was used as a source of AChE; rat serum was the source of BChE.AChE was assayed spectrophotometrically with acetylthiocholine assubstrate, in the presence of 10⁻⁴ M ethopropazine as BChE inhibitor (G.L. Ellman et al., Biochem. Pharmacol., 7, 88 (1961). BChE was assayedsimilarly with butyrylthiocholine as substrate and 10⁻⁵ M BW284C51 asAChE inhibitor. The measured IC₅₀ values for inhibitions of AChE and arelated enzyme, butyrylcholinesterase (BChE), are listed in Table

                  TABLE I                                                         ______________________________________                                        IC.sub.50 of THA and Analogs                                                  for Inhibition of AChE and BChE.                                                        rat brain                                                                             IC.sub.50 (nM)                                                        AChE    rat serum BChE                                                                            Selectivity.sup.†                        ______________________________________                                                 THA    250        40       0.2                                       Class 1. 1a     0.2       315       1369.6                                             1b     0.5       216       432.0                                              1c     0.5       202       404.0                                              1d     2.0       360       180.0                                     Class 2. 2a     1500      NA*       NA                                                 2b     1500      500       0.3                                                2c     520       800       1.5                                                2d     360       1000      2.8                                                2e     220       2000      9.1                                                2f     3000      10,000    3.3                                                2g     3000      NA        NA                                        ______________________________________                                         *NA: Not available                                                            .sup.† Selectivity: IC.sub.50 BChE divided by IC.sub.50 for AChE. 

As compared with THA, compound 1a proved 1000 times more potent and 7000times more selective in inhibiting rat brain AChE (FIG. 5). Inhibitorypotency was inversely related to the length of the alkylene chain.Optimal chain length for this series was reached in compound 1a, with 7methylene groups between THA residues.

For a rigorous test of the compounds' anticholinesterase properties, thesubstrate-kinetics of enzyme inhibition were examined in a highlypurified preparation of human brain AChE. AChE was highly purified fromautopsied human cerebellum by affinity chromatography on procainamideSepharose, essentially as described by D. de la Hoz et al., Life Sci.39, 195 (1986). Enzyme activity was measured as described supra, exceptthat acetylthiocholine concentration was varied. Reciprocal velocity wasplotted against reciprocal substrate concentration in the presence ofvarying concentrations of compound 1a (FIG. 6, Panel A) and THA (FIG. 6,Panel B). On the right, K_(i) values for the two AChE inhibitors weretaken from the negative X-intercepts of the slope replots. According tothe reciprocal slope-replot procedure of I. H. Segel, Enzyme Kinetics,170 (1975), class 1 analogs, like THA itself, produced a linear mixedtype of enzyme inhibition. The calculated K_(i) for compound 1a was 1.4nM. This value is well below the 80 nM K_(i) determined for THA in thesame AChE preparation. It does appear that THA inhibits human AChE morereadily than rat AChE, at which its K_(i) is nearly micromolar. Even so,the results conclusively demonstrate the superior potency ofbis-functional analogs as inhibitors of AChE in the mammalian brain.

Inhibition curves of "class 2" analogs (FIG. 5) showed that compound 2ewas the most potent: further decrease or increase of chain lengthweakened AChE inhibition. This result confirmed that the chain length ofbis-aromatic THA analogs is an important determinant of potency. Inparticular, a spacing of 7 methylene units between THA and tolueneresidues of the class 2 compounds was consistently associated withmaximal effect on the catalytic function of AChE. Thus, modification ofthe spacer chain can serve as a molecular "switch" for the property ofAChE inhibition.

It is striking that, when tested against rat brain AChE, compound 2e andTHA were nearly equipotent inhibitors and were weaker than compound 1a.The dramatic increase in inhibitory potency conferred by the additionalTHA residue in compound 1a may reflect facilitation in binding.

In addition, lipophilicity of compounds 1 and 2 was confirmed to beincreased over THA. This is evidenced by that these compounds in theirsalt form were not completely dissolved in the ethanol-containingaqueous solution until the percentage of EtOH was raised to 40%, whileTHA in its salt form was readily dissolved in the ethanol-free aqueoussolution. The results of these biological evaluations demonstrate thatthe present compounds can be used for one or more of the above-mentionedapplications, because of (i) their greatly improved potency andselectivity to ACHE inhibition; (ii) their increased hydrophobicity, and(iii) their efficient and economical synthesis.

All publications, patents and patent documents are incorporated byreference herein, as though individually incorporated by reference. Theinvention has been described with reference to various specific andpreferred embodiments and techniques. However, it should be understoodthat many variations and modifications may be made while remainingwithin the spirit and scope of the invention.

What is claimed is:
 1. A compound of the general formula (I): ##STR5##wherein R is H or (C₁ -C₄)alkyl, Y is (C₄ -C₁₅)alkylene or (C₄-C₁₅)alkylene N(R) and Z is 1,2,3,4-tetrahydroacridin-9-yl; or apharmaceutically acceptable salt thereof.
 2. A compound of claim 1wherein R is H.
 3. A compound of claim 1 wherein Y is (C₄ -C₁₂)alkyleneor (C₄ -C₁₂)alkylene N(R).
 4. The compound of claim 3 wherein Y is--(CH₂)_(n) -- or --(CH₂)_(n) --N(R)--, wherein n is 6-10. 5.1,ω-n-alkylene-bis-9,9'-amino-1,2,3,4-tetrahydroacridine, wherein n is7-10.
 6. A pharmaceutical composition comprising an effective AChE orBChE inhibitory amount of a compound of claim 1 in combination with apharmaceutically acceptable carrier.
 7. The composition of claim 6 whichis adapted for oral administration.
 8. The composition of claim 6 whichis adapted for parenteral administration.
 9. An insecticidal orparasiticidal composition comprising an effective AChE inhibitory amountof a compound of claim 1 in combination with a carrier vehicle.
 10. Thecomposition of claim 9 wherein the carrier vehicle is a finely dividedinert solid.
 11. The composition of claim 9 wherein the carrier vehicleis a liquid vehicle.
 12. A method for inhibiting cholinesterase activityin a human afflicted with a condition which is ameliorated bycholinesterase inhibition comprising administering an amount of acompound of claim 1 effective to inhibit said activity.
 13. The methodof claim 12 wherein the cholinesterase is AChE.
 14. The method of claim12 wherein the cholinesterase is BChE.